This Program Project represents a cohesive group of laboratories and investigators that share common goals and strategies aimed at transferring genes to progenitor and differentiated cells. These laboratories also share a need for several techniques such as the creation of gene transfer vectors and the analysis of data generated by gene transfer studies. The Cell Biology Core Facility aims to provide this group of investigators with a variety of imaging and detection methods to show interaction of vectors with target cells, expression of vector-encoded transgenes, and the physiological impact of transgene expression. Toward this end, the Cell Biology Core FaCility maintains state-of-the-art equipment for fluorescence detection, optimal filters and documentation equipment for brightfield and fluorescence image acquisition, and facilitated access to additional medical Center resources such as histological, ultrastructural, and con focal facilities. Furthermore, the staff of the Cell Biology Core Facility has extensive training in a variety of cytological and histological techniques and will dedicate time and resources to make those assets available to the participating Projects and Pilots. The goal of this Core Facility as well as the other core facilities associated with the Program Project will be realized in making the whole of this research endeavor greater than the sum of its parts.